When a motor vehicle is involved in an accident, the standard automotive lap and shoulder belt restraint system, if properly used, provides a minimum level of protection from crash injury to the passengers or driver as required by Federal Motor Vehicle Safety Standard number 208—Occupant Crash Protection. This minimum level of protection is currently required for adult passengers and drivers who are either a 5.sup.th percentile adult female or a 50.sup.th percentile adult male. For persons who are smaller than a 5.sup.th percentile adult female, supplemental restraint devices are required to provide a minimum level of protection pursuant to Federal Motor Vehicle Safety Standard 213. There are currently no motor vehicle safety standards relating to adults larger than a 50.sup.th percentile male adult, or to a pregnant woman of any size and her unborn child(ren).
The purpose of the “Method For Supplemental Automotive Restraint For Pregnant Women” (Method/Device) is to provide enhanced protection for the pregnant mother and her unborn child(ren).
There are several categories of injuries that occur to lap and shoulder belted occupants in motor vehicle crashes. One category results from violent contact with the steering wheel, the inner door surfaces and related components, the dashboard area and related components, the windshield, side windows and their related frames, and other objects. A second category involves injuries caused by inflating air bags, and a third category involves injuries caused by the lap and shoulder belts. These belt-induced injuries are commonly referred as “Seat Belt Syndrome”. “Seat Belt Syndrome” injuries are signified by skin abrasions of the neck, chest, and abdomen, which indicate internal injury in approximately 30% of cases. Neck abrasions are associated with injuries to the carotid artery, larynx, and cervical spine. Chest abrasions are associated with fractures of the sternum, ribs, and clavicles, and injuries to the lungs, heart and thoracic aorta. Abdominal abrasions are associated with mesenteric tears, bowel perforation and hematoma, injuries to the abdominal aorta and injuries to the spine, spinal cord, and pelvis..sup.i These injuries are exacerbated when the lap belt slips up over the pelvis and into the lower abdominal cavity. This is commonly referred to as “submarining”, and it is the natural tendency and a frequent occurrence in motor vehicle crashes and at other times. .sup.iHayes, Conway, Walsh, Coppage, & Gervin, “Seat Belt Injuries: Radiologic and Clinical Correlation”, Department of Radiology, Medical College of Virginia, Radiographics, January 1991, 11(1):23-36
There are two categories of forces between the seat belts and the body of the person. The first involves the static forces that are intended to hold the belts in place during normal vehicle operations. These static forces are typically provided by a seat belt retractor or similar device. These forces are minimal in the absence of a crash or other abrupt motion change (acceleration) of the vehicle, and are associated primarily with the comfort of the passenger. They are inconsequential in causing injury to the passenger provided that they maintain the belts in the proper position prior to the crash.
The second category of force between the seat belts and the body of the person involves the dynamic forces between the surface of the body and the lap and shoulder belts as required to restrain the body in the vehicle during the abrupt motions of crash or other event. These forces exist only when the vehicle is undergoing a crash or other abrupt motion change (acceleration).
Seat Belt Syndrome injuries result from this second category of dynamic forces. These forces are applied to the limited area of direct contact between the belts and the surface of the body. The application of these high dynamic forces to the limited area of contact between the belts and the person's body causes high stresses and strains in various parts of the body, which are the root causes of Seat Belt Syndrome injuries.
The mechanisms of injury to the fetus are less well documented, but the risk of injury is clearly extended to the unborn child. Of pregnant women who are treated for injury in hospital emergency departments, “Motor Vehicle occupant injuries were the leading mechanism of emergency department injury-related visits . . . . Pregnant women with an injury-related emergency department visit were more likely than non-injured pregnant women to experience pre-term labor, placental abruption, and cesarean delivery..sup.ii .sup.iiWeiss, Sauber-Schatz and Cook, “The Epidemiology of Pregnancy-Associated Emergency Department Injury Visits and their Impact on Birth Outcomes”, Accident Analysis and Prevention, Volume 40, Issue 3, May, 2008, pp. 1088-1095.
The unborn child is at risk because the mother's abdomen provides limited protection against objects that impinge on the abdomen, such as the steering wheel, lap and shoulder belts, air bag restraints, door handles and other objects and surfaces within the vehicle that are likely to contact and apply force to the mother's body in both accident and non-accident situations. In particular, the lap and shoulder belts, steering wheel and air bags are designed to protect the mother. They also provide some protection to the fetus, but in addition, all three pose additional side effect risks of injury to the fetus.